While talking to CNBC India on Friday, the billionaire banker said the recent proliferation of initial coin offerings, a red-hot cryptocurrency-based fundraising method, and digital coins like bitcoin concerns him.

"It's creating something out of nothing that to me is worth nothing," Dimon said."It'll end when people lose a lot of money."

To raise money through an ICO, companies create their own digital coin or token. Investors have poured into ICOs this year with some companies raising millions of dollars in a matter of seconds from token sales.

Aaron Lasher, the chief marketing office at Breadwallet, a bitcoin technology company, told Business Insider that Dimon's comments don't surprise him because digital currencies are a direct attack on his business.

"Every dollar in cryptocurrency is another dollar in value that JPMorgan cannot monetize," Lasher said. "What does it mean when a software company 'manages' as much money as a traditional bank?"